1. Field of the Invention
The present invention relates to a reinforcement device for a lateral buckling stress installed on an angle-type steel member so as to be attachable and detachable therefrom without power-off of a power line tower, preparation and disassembly of members in order to prevent lateral buckling and accidental torsion.
2. Description of the Related Art
Generally, a power line tower is configured as a truss structure. The truss structure can withstand external forces by using the tension and compressive force of steel members by connecting the steel members to each other in a triangular shape, and can be lighter and stronger. Thus, the truss structure is effective against an earthquake. An angle-type steel member is used as steel member used in the power line tower having the truss structure, and is used as a brace for withstanding a lateral force used in a steel structure.
However, the angle-type steel member is vulnerable to lateral buckling and accidental torsion. When one angle-type steel member of any structure begins to buckle due to accidental typhoon or gust, other angle-type steel members collapse consecutively. Thus, the management of the angle-type steel member is very important in such a way that the angle-type steel member may not be bent and distorted.
That is, as shown in FIG. 1, when the angle-type steel member (‘L’ type steel main post member) has a relatively great length compared to a width of a cross-section, compressive load acts on both ends of the angle-type steel member, and thus lateral buckling by which a post buckles suddenly occurs when the compressive load reaches a predetermined intensity.
In order to reinforce a lateral buckling stress, a member having a great cross-section is replaced with the angle-type steel member with a weak lateral buckling stress, or backplates are bonded to the angle-type steel member. However, in these methods, preparation operations such as power-off of a power line tower, installment of a bypass reinforcement member and disassembly of members are required. In addition, lots of time and costs are incurred for detours of power lines, drawings and preparation when the angle-type steel member with a weak lateral buckling stress is used.